The present invention relates to a hollow filament module comprising an annular passage of hollow filaments having a longitudinal axis and an axially extending flow channel formed of a hardened mass, whereby hollow filaments of curved form and substantially equal lengths are arranged in substantially radial direction in planes including with the longitudinal axis substantially angles of 90.degree. and in which the hollow filaments in adjacent planes cross each each other and engage each other at the crossing point thereof, at which both ends of each hollow filament are in such a manner embedded and exposed in the hard mass so that fluid may flow therethrough, and in which hollow filaments communicate with the axially extending flow channel.
Devices in which material or heat transmission through the wall of hollow filaments occurs, which eventually acts as a membrane, are known per se. It is also known to arrange the used hollow filaments in the form of hollow filament modules, which, similar to known filter cartridges, after extended use may quickly and simply be exchanged for new or regenerated hollow filament modules. Such filament modules find increasing use in various technical and medical fields, whereby depending on the composition of the hollow filaments heat transmission, material exchange, material separation or a combination of such transactions is carried out.
In all the cases in which a cleaning or regeneration of the soiled or exhausted hollow filament modules is not possible, and in which the same have to be discarded after extended use, there existed the demand for such hollow filament modules which, on the one hand, are universally usable and which have a high efficiency and which, on the other hand, can be constructed in a simple manner and with reasonable costs.
A hollow filament module of the aforementioned kind is disclosed in U.S. Pat. No. 3,198,335. This known hollow filament module has, however, the disadvantage that only two fluids may be used for heat or material transmission, whereby one of the fluids passes through the hollow filaments whereas the other fluid flows around the hollow filaments. Furthermore, since the length of the hollow filaments is twice the thickness of the hollow filament package in radial direction, the pressure losses in the hollow filaments are correspondingly rather high, and the fluid flowing therethrough correspondingly rather small, so that the exchange output is unsatisfactory. When using this known module as a heat exchanger, there occurs also, due to the return flow of the fluid passing through the hollow filaments to the center, a return exchange.